50648-94-7Relevant academic research and scientific papers
Chemical Synthesis of Side-Chain-Hydroxylated Vitamin D3 Derivatives and Their Metabolism by CYP27B1
Iwaki, Miho,Mizumoto, Yuka,Nagasawa, Kazuo,Nagata, Akiko,Ohshita, Haruki,Sakaki, Toshiyuki,Sakamoto, Ryota,Yasuda, Kaori
, p. 2896 - 2900 (2021/07/31)
1α,25-Dihydroxyvitamin D3 (abbreviated here as 1,25D3) is a hormonally active form of vitamin D3 (D3), and is produced from D3 by CYP27 A1-mediated hydroxylation at C25, followed by CYP27B1-mediated hydroxylation at C1. Further hydroxylation of 25D3 and 1,25D3 occurs at C23, C24 and C26 to generate corresponding metabolites, except for 1,25R,26D3. Since the capability of CYP27B1 to hydroxylate C1 of side-chain-hydroxylated metabolites other than 23S,25D3 and 24R,25D3 has not been examined, we have here explored the role of CYP27B1 in the C1 hydroxylation of a series of side-chain-hydroxylated D3 derivatives. We found that CYP27B1 hydroxylates the R diastereomers of 24,25D3 and 25,26D3 more effectively than the S diastereomers, but shows almost no activity towards either diastereomer of 23,25D3. This is the first report to show that CYP27B1 metabolizes 25,26D3 to the corresponding 1α-hydroxylated derivative, 1,25,26D3. It will be interesting to examine the physiological relevance of this finding.
A new insight into the role of rat cytochrome P450 24A1 in metabolism of selective analogs of 1α,25-dihydroxyvitamin D3
Rhieu, Steve Y.,Annalora, Andrew J.,Gathungu, Rose M.,Vouros, Paul,Uskokovic, Milan R.,Schuster, Inge,Palmore, G. Tayhas R.,Reddy, G. Satyanarayana
experimental part, p. 33 - 43 (2012/03/07)
We examined the metabolism of two synthetic analogs of 1α,25- dihydroxyvitamin D3 (1), namely 1α,25-dihydroxy-16-ene-23-yne- vitamin D3 (2) and 1α,25-dihydroxy-16-ene-23-yne-26,27- dimethyl-vitamin D3 (4) using rat cytochrome P450 24A1 (CYP24A1) in a reconstituted system. We noted that 2 is metabolized into a single metabolite identified as C26-hydroxy-2 while 4 is metabolized into two metabolites, identified as C26-hydroxy-4 and C26a-hydroxy-4. The structural modification of adding methyl groups to the side chain of 1 as in 4 is also featured in another analog, 1α,25-dihydroxy-22,24-diene-24,26,27-trihomo-vitamin D3 (6). In a previous study, 6 was shown to be metabolized exactly like 4, however, the enzyme responsible for its metabolism was found to be not CYP24A1. To gain a better insight into the structural determinants for substrate recognition of different analogs, we performed an in silico docking analysis using the crystal structure of rat CYP24A1 that had been solved for the substrate-free open form. Whereas analogs 2 and 4 docked similar to 1, 6 showed altered interactions for both the A-ring and side chain, despite prototypical recognition of the CD-ring. These findings hint that CYP24A1 metabolizes selectively different analogs of 1, based on their ability to generate discrete recognition cues required to close the enzyme and trigger the catalytic mechanism.
Metabolism of substrates incorporated into phospholipid vesicles by mouse 25-hydroxyvitamin D3 1α-hydroxylase (CYP27B1)
Tang, Edith K.Y.,Voo, Kimberley J.Q.,Nguyen, Minh N.,Tuckey, Robert C.
experimental part, p. 171 - 179 (2011/02/23)
CYP27B1 catalyzes the 1α-hydroxylation of 25-hydroxyvitamin D3 to 1α,25-dihydroxyvitamin D3, the hormonally active form of vitamin D3. To further characterize mouse CYP27B1, it was expressed in Escherichia coli, purified and its activity measured on substrates incorporated into phospholipid vesicles, which served as a model of the inner mitochondrial membrane. 25-Hydroxyvitamin D3 and 25-hydroxyvitamin D2 in vesicles underwent 1α-hydroxylation with similar kinetics, the catalytic rate constants (kcat) were 41 and 48mol/min/mol P450, respectively, while Km values were 5.9 and 4.6mmol/mol phospholipid, respectively. CYP27B1 showed inhibition when substrate concentrations in the membrane were greater than 4 times Km, more pronounced with 25-hydroxyvitamin D3 than 25-hydroxyvitamin D2. Higher catalytic efficiency was seen in vesicles prepared from dioleoyl phosphatidylcholine and cardiolipin than for dimyristoyl phosphatidylcholine vesicles. CYP27B1 also catalyzed 1α-hydroxylation of vesicle-associated 24R,25-dihydroxyvitamin D3 and 20-hydroxyvitamin D3, and 25-hydroxylation of 1α-hydroxyvitamin D3 and 1α-hydroxyvitamin D2, but with much lower efficiency than for 25(OH)D3. This study shows that CYP27B1 can hydroxylate 25-hydroxyvitamin D2 and 25-hydroxyvitamin D3 associated with phospholipid membranes with the highest activity yet reported for the enzyme. The expressed enzyme has low activity at higher concentrations of 25-hydroxyvitamin D in membranes, revealing that substrate inhibition may contribute to the regulation of the activity of this enzyme.
Stereoselective convergent synthesis of 24,25-dihydroxyvitamin D3 metabolites: a practical approach.
Perez Sestelo, Jose,Cornella, Ivan,de Una, Olga,Mourino, Antonio,Sarandeses, Luis A
, p. 2747 - 2752 (2007/10/03)
Vitamin D3 active metabolites 24R,25-(OH)2-D3, 24S,25-(OH)2-D3, and 1 alpha, 24R,25-(OH)3-D3 were synthesized by a convergent and stereoselective approach. In the synthetic route, the stereogenic center at C-24 was generated through ultrasonically induced aqueous conjugate addition of iodide 6 to Seebach's dioxolanone 5, and the vitamin D triene system was constructed using the Lythgoe approach. The synthesis, which is both short (seven steps from iodide 6) and efficient (32-40% overall yield), allows the preparation of large quantities of the metabolites and provides a novel example of a highly stereoselective reaction promoted by the zinc-copper couple in aqueous media.
